PLATE LXXXIII 



EVOLUTION OF THE EYES ON THE WING-FEATHERS 

 OF THE ARGUS PHEASANT 



The gradual development of the ocelli or eyed spots on the secondary wing-feathers is beautifully 

 shown by the successive feathers themselves. Starting as a slight irregularity in the buff markings, the 

 next stage shows two of these lines approaching and enclosing a dull reddish-brown stain. This takes form 

 roughly circular, acquires a frame, and finally evolves into the marvellous eyes, large, round, illuminated 

 from one side, shaded, so that when the feather is slightly vibrated they appear to revolve swiftly, like 

 brilliant balls suspended In darkened sockets. These are all unquestionably brought into play in courtship, 

 but the object of the delicate detail is a mystery, for it certainly does not affect the hen directly, either 

 by artistic design or harmonious colour. 



